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Diffstat (limited to 'contrib/llvm/lib/Transforms/Utils/VNCoercion.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/Utils/VNCoercion.cpp | 539 | 
1 files changed, 0 insertions, 539 deletions
diff --git a/contrib/llvm/lib/Transforms/Utils/VNCoercion.cpp b/contrib/llvm/lib/Transforms/Utils/VNCoercion.cpp deleted file mode 100644 index a77bf50fe10b..000000000000 --- a/contrib/llvm/lib/Transforms/Utils/VNCoercion.cpp +++ /dev/null @@ -1,539 +0,0 @@ -#include "llvm/Transforms/Utils/VNCoercion.h" -#include "llvm/Analysis/AliasAnalysis.h" -#include "llvm/Analysis/ConstantFolding.h" -#include "llvm/Analysis/MemoryDependenceAnalysis.h" -#include "llvm/Analysis/ValueTracking.h" -#include "llvm/IR/IRBuilder.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/Support/Debug.h" - -#define DEBUG_TYPE "vncoerce" -namespace llvm { -namespace VNCoercion { - -/// Return true if coerceAvailableValueToLoadType will succeed. -bool canCoerceMustAliasedValueToLoad(Value *StoredVal, Type *LoadTy, -                                     const DataLayout &DL) { -  Type *StoredTy = StoredVal->getType(); -  if (StoredTy == LoadTy) -    return true; - -  // If the loaded or stored value is an first class array or struct, don't try -  // to transform them.  We need to be able to bitcast to integer. -  if (LoadTy->isStructTy() || LoadTy->isArrayTy() || StoredTy->isStructTy() || -      StoredTy->isArrayTy()) -    return false; - -  uint64_t StoreSize = DL.getTypeSizeInBits(StoredTy); - -  // The store size must be byte-aligned to support future type casts. -  if (llvm::alignTo(StoreSize, 8) != StoreSize) -    return false; - -  // The store has to be at least as big as the load. -  if (StoreSize < DL.getTypeSizeInBits(LoadTy)) -    return false; - -  // Don't coerce non-integral pointers to integers or vice versa. -  if (DL.isNonIntegralPointerType(StoredVal->getType()->getScalarType()) != -      DL.isNonIntegralPointerType(LoadTy->getScalarType())) { -    // As a special case, allow coercion of memset used to initialize -    // an array w/null.  Despite non-integral pointers not generally having a -    // specific bit pattern, we do assume null is zero. -    if (auto *CI = dyn_cast<Constant>(StoredVal)) -      return CI->isNullValue(); -    return false; -  } -   -  return true; -} - -template <class T, class HelperClass> -static T *coerceAvailableValueToLoadTypeHelper(T *StoredVal, Type *LoadedTy, -                                               HelperClass &Helper, -                                               const DataLayout &DL) { -  assert(canCoerceMustAliasedValueToLoad(StoredVal, LoadedTy, DL) && -         "precondition violation - materialization can't fail"); -  if (auto *C = dyn_cast<Constant>(StoredVal)) -    if (auto *FoldedStoredVal = ConstantFoldConstant(C, DL)) -      StoredVal = FoldedStoredVal; - -  // If this is already the right type, just return it. -  Type *StoredValTy = StoredVal->getType(); - -  uint64_t StoredValSize = DL.getTypeSizeInBits(StoredValTy); -  uint64_t LoadedValSize = DL.getTypeSizeInBits(LoadedTy); - -  // If the store and reload are the same size, we can always reuse it. -  if (StoredValSize == LoadedValSize) { -    // Pointer to Pointer -> use bitcast. -    if (StoredValTy->isPtrOrPtrVectorTy() && LoadedTy->isPtrOrPtrVectorTy()) { -      StoredVal = Helper.CreateBitCast(StoredVal, LoadedTy); -    } else { -      // Convert source pointers to integers, which can be bitcast. -      if (StoredValTy->isPtrOrPtrVectorTy()) { -        StoredValTy = DL.getIntPtrType(StoredValTy); -        StoredVal = Helper.CreatePtrToInt(StoredVal, StoredValTy); -      } - -      Type *TypeToCastTo = LoadedTy; -      if (TypeToCastTo->isPtrOrPtrVectorTy()) -        TypeToCastTo = DL.getIntPtrType(TypeToCastTo); - -      if (StoredValTy != TypeToCastTo) -        StoredVal = Helper.CreateBitCast(StoredVal, TypeToCastTo); - -      // Cast to pointer if the load needs a pointer type. -      if (LoadedTy->isPtrOrPtrVectorTy()) -        StoredVal = Helper.CreateIntToPtr(StoredVal, LoadedTy); -    } - -    if (auto *C = dyn_cast<ConstantExpr>(StoredVal)) -      if (auto *FoldedStoredVal = ConstantFoldConstant(C, DL)) -        StoredVal = FoldedStoredVal; - -    return StoredVal; -  } -  // If the loaded value is smaller than the available value, then we can -  // extract out a piece from it.  If the available value is too small, then we -  // can't do anything. -  assert(StoredValSize >= LoadedValSize && -         "canCoerceMustAliasedValueToLoad fail"); - -  // Convert source pointers to integers, which can be manipulated. -  if (StoredValTy->isPtrOrPtrVectorTy()) { -    StoredValTy = DL.getIntPtrType(StoredValTy); -    StoredVal = Helper.CreatePtrToInt(StoredVal, StoredValTy); -  } - -  // Convert vectors and fp to integer, which can be manipulated. -  if (!StoredValTy->isIntegerTy()) { -    StoredValTy = IntegerType::get(StoredValTy->getContext(), StoredValSize); -    StoredVal = Helper.CreateBitCast(StoredVal, StoredValTy); -  } - -  // If this is a big-endian system, we need to shift the value down to the low -  // bits so that a truncate will work. -  if (DL.isBigEndian()) { -    uint64_t ShiftAmt = DL.getTypeStoreSizeInBits(StoredValTy) - -                        DL.getTypeStoreSizeInBits(LoadedTy); -    StoredVal = Helper.CreateLShr( -        StoredVal, ConstantInt::get(StoredVal->getType(), ShiftAmt)); -  } - -  // Truncate the integer to the right size now. -  Type *NewIntTy = IntegerType::get(StoredValTy->getContext(), LoadedValSize); -  StoredVal = Helper.CreateTruncOrBitCast(StoredVal, NewIntTy); - -  if (LoadedTy != NewIntTy) { -    // If the result is a pointer, inttoptr. -    if (LoadedTy->isPtrOrPtrVectorTy()) -      StoredVal = Helper.CreateIntToPtr(StoredVal, LoadedTy); -    else -      // Otherwise, bitcast. -      StoredVal = Helper.CreateBitCast(StoredVal, LoadedTy); -  } - -  if (auto *C = dyn_cast<Constant>(StoredVal)) -    if (auto *FoldedStoredVal = ConstantFoldConstant(C, DL)) -      StoredVal = FoldedStoredVal; - -  return StoredVal; -} - -/// If we saw a store of a value to memory, and -/// then a load from a must-aliased pointer of a different type, try to coerce -/// the stored value.  LoadedTy is the type of the load we want to replace. -/// IRB is IRBuilder used to insert new instructions. -/// -/// If we can't do it, return null. -Value *coerceAvailableValueToLoadType(Value *StoredVal, Type *LoadedTy, -                                      IRBuilder<> &IRB, const DataLayout &DL) { -  return coerceAvailableValueToLoadTypeHelper(StoredVal, LoadedTy, IRB, DL); -} - -/// This function is called when we have a memdep query of a load that ends up -/// being a clobbering memory write (store, memset, memcpy, memmove).  This -/// means that the write *may* provide bits used by the load but we can't be -/// sure because the pointers don't must-alias. -/// -/// Check this case to see if there is anything more we can do before we give -/// up.  This returns -1 if we have to give up, or a byte number in the stored -/// value of the piece that feeds the load. -static int analyzeLoadFromClobberingWrite(Type *LoadTy, Value *LoadPtr, -                                          Value *WritePtr, -                                          uint64_t WriteSizeInBits, -                                          const DataLayout &DL) { -  // If the loaded or stored value is a first class array or struct, don't try -  // to transform them.  We need to be able to bitcast to integer. -  if (LoadTy->isStructTy() || LoadTy->isArrayTy()) -    return -1; - -  int64_t StoreOffset = 0, LoadOffset = 0; -  Value *StoreBase = -      GetPointerBaseWithConstantOffset(WritePtr, StoreOffset, DL); -  Value *LoadBase = GetPointerBaseWithConstantOffset(LoadPtr, LoadOffset, DL); -  if (StoreBase != LoadBase) -    return -1; - -  // If the load and store are to the exact same address, they should have been -  // a must alias.  AA must have gotten confused. -  // FIXME: Study to see if/when this happens.  One case is forwarding a memset -  // to a load from the base of the memset. - -  // If the load and store don't overlap at all, the store doesn't provide -  // anything to the load.  In this case, they really don't alias at all, AA -  // must have gotten confused. -  uint64_t LoadSize = DL.getTypeSizeInBits(LoadTy); - -  if ((WriteSizeInBits & 7) | (LoadSize & 7)) -    return -1; -  uint64_t StoreSize = WriteSizeInBits / 8; // Convert to bytes. -  LoadSize /= 8; - -  bool isAAFailure = false; -  if (StoreOffset < LoadOffset) -    isAAFailure = StoreOffset + int64_t(StoreSize) <= LoadOffset; -  else -    isAAFailure = LoadOffset + int64_t(LoadSize) <= StoreOffset; - -  if (isAAFailure) -    return -1; - -  // If the Load isn't completely contained within the stored bits, we don't -  // have all the bits to feed it.  We could do something crazy in the future -  // (issue a smaller load then merge the bits in) but this seems unlikely to be -  // valuable. -  if (StoreOffset > LoadOffset || -      StoreOffset + StoreSize < LoadOffset + LoadSize) -    return -1; - -  // Okay, we can do this transformation.  Return the number of bytes into the -  // store that the load is. -  return LoadOffset - StoreOffset; -} - -/// This function is called when we have a -/// memdep query of a load that ends up being a clobbering store. -int analyzeLoadFromClobberingStore(Type *LoadTy, Value *LoadPtr, -                                   StoreInst *DepSI, const DataLayout &DL) { -  auto *StoredVal = DepSI->getValueOperand(); -   -  // Cannot handle reading from store of first-class aggregate yet. -  if (StoredVal->getType()->isStructTy() || -      StoredVal->getType()->isArrayTy()) -    return -1; - -  // Don't coerce non-integral pointers to integers or vice versa. -  if (DL.isNonIntegralPointerType(StoredVal->getType()->getScalarType()) != -      DL.isNonIntegralPointerType(LoadTy->getScalarType())) { -    // Allow casts of zero values to null as a special case -    auto *CI = dyn_cast<Constant>(StoredVal); -    if (!CI || !CI->isNullValue()) -      return -1; -  } - -  Value *StorePtr = DepSI->getPointerOperand(); -  uint64_t StoreSize = -      DL.getTypeSizeInBits(DepSI->getValueOperand()->getType()); -  return analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, StorePtr, StoreSize, -                                        DL); -} - -/// This function is called when we have a -/// memdep query of a load that ends up being clobbered by another load.  See if -/// the other load can feed into the second load. -int analyzeLoadFromClobberingLoad(Type *LoadTy, Value *LoadPtr, LoadInst *DepLI, -                                  const DataLayout &DL) { -  // Cannot handle reading from store of first-class aggregate yet. -  if (DepLI->getType()->isStructTy() || DepLI->getType()->isArrayTy()) -    return -1; - -  // Don't coerce non-integral pointers to integers or vice versa. -  if (DL.isNonIntegralPointerType(DepLI->getType()->getScalarType()) != -      DL.isNonIntegralPointerType(LoadTy->getScalarType())) -    return -1; - -  Value *DepPtr = DepLI->getPointerOperand(); -  uint64_t DepSize = DL.getTypeSizeInBits(DepLI->getType()); -  int R = analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, DepPtr, DepSize, DL); -  if (R != -1) -    return R; - -  // If we have a load/load clobber an DepLI can be widened to cover this load, -  // then we should widen it! -  int64_t LoadOffs = 0; -  const Value *LoadBase = -      GetPointerBaseWithConstantOffset(LoadPtr, LoadOffs, DL); -  unsigned LoadSize = DL.getTypeStoreSize(LoadTy); - -  unsigned Size = MemoryDependenceResults::getLoadLoadClobberFullWidthSize( -      LoadBase, LoadOffs, LoadSize, DepLI); -  if (Size == 0) -    return -1; - -  // Check non-obvious conditions enforced by MDA which we rely on for being -  // able to materialize this potentially available value -  assert(DepLI->isSimple() && "Cannot widen volatile/atomic load!"); -  assert(DepLI->getType()->isIntegerTy() && "Can't widen non-integer load"); - -  return analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, DepPtr, Size * 8, DL); -} - -int analyzeLoadFromClobberingMemInst(Type *LoadTy, Value *LoadPtr, -                                     MemIntrinsic *MI, const DataLayout &DL) { -  // If the mem operation is a non-constant size, we can't handle it. -  ConstantInt *SizeCst = dyn_cast<ConstantInt>(MI->getLength()); -  if (!SizeCst) -    return -1; -  uint64_t MemSizeInBits = SizeCst->getZExtValue() * 8; - -  // If this is memset, we just need to see if the offset is valid in the size -  // of the memset.. -  if (MI->getIntrinsicID() == Intrinsic::memset) { -    if (DL.isNonIntegralPointerType(LoadTy->getScalarType())) { -      auto *CI = dyn_cast<ConstantInt>(cast<MemSetInst>(MI)->getValue()); -      if (!CI || !CI->isZero()) -        return -1; -    } -    return analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, MI->getDest(), -                                          MemSizeInBits, DL); -  } - -  // If we have a memcpy/memmove, the only case we can handle is if this is a -  // copy from constant memory.  In that case, we can read directly from the -  // constant memory. -  MemTransferInst *MTI = cast<MemTransferInst>(MI); - -  Constant *Src = dyn_cast<Constant>(MTI->getSource()); -  if (!Src) -    return -1; - -  GlobalVariable *GV = dyn_cast<GlobalVariable>(GetUnderlyingObject(Src, DL)); -  if (!GV || !GV->isConstant() || !GV->hasDefinitiveInitializer()) -    return -1; - -  // See if the access is within the bounds of the transfer. -  int Offset = analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, MI->getDest(), -                                              MemSizeInBits, DL); -  if (Offset == -1) -    return Offset; - -  // Don't coerce non-integral pointers to integers or vice versa, and the -  // memtransfer is implicitly a raw byte code -  if (DL.isNonIntegralPointerType(LoadTy->getScalarType())) -    // TODO: Can allow nullptrs from constant zeros -    return -1; - -  unsigned AS = Src->getType()->getPointerAddressSpace(); -  // Otherwise, see if we can constant fold a load from the constant with the -  // offset applied as appropriate. -  Src = -      ConstantExpr::getBitCast(Src, Type::getInt8PtrTy(Src->getContext(), AS)); -  Constant *OffsetCst = -      ConstantInt::get(Type::getInt64Ty(Src->getContext()), (unsigned)Offset); -  Src = ConstantExpr::getGetElementPtr(Type::getInt8Ty(Src->getContext()), Src, -                                       OffsetCst); -  Src = ConstantExpr::getBitCast(Src, PointerType::get(LoadTy, AS)); -  if (ConstantFoldLoadFromConstPtr(Src, LoadTy, DL)) -    return Offset; -  return -1; -} - -template <class T, class HelperClass> -static T *getStoreValueForLoadHelper(T *SrcVal, unsigned Offset, Type *LoadTy, -                                     HelperClass &Helper, -                                     const DataLayout &DL) { -  LLVMContext &Ctx = SrcVal->getType()->getContext(); - -  // If two pointers are in the same address space, they have the same size, -  // so we don't need to do any truncation, etc. This avoids introducing -  // ptrtoint instructions for pointers that may be non-integral. -  if (SrcVal->getType()->isPointerTy() && LoadTy->isPointerTy() && -      cast<PointerType>(SrcVal->getType())->getAddressSpace() == -          cast<PointerType>(LoadTy)->getAddressSpace()) { -    return SrcVal; -  } - -  uint64_t StoreSize = (DL.getTypeSizeInBits(SrcVal->getType()) + 7) / 8; -  uint64_t LoadSize = (DL.getTypeSizeInBits(LoadTy) + 7) / 8; -  // Compute which bits of the stored value are being used by the load.  Convert -  // to an integer type to start with. -  if (SrcVal->getType()->isPtrOrPtrVectorTy()) -    SrcVal = Helper.CreatePtrToInt(SrcVal, DL.getIntPtrType(SrcVal->getType())); -  if (!SrcVal->getType()->isIntegerTy()) -    SrcVal = Helper.CreateBitCast(SrcVal, IntegerType::get(Ctx, StoreSize * 8)); - -  // Shift the bits to the least significant depending on endianness. -  unsigned ShiftAmt; -  if (DL.isLittleEndian()) -    ShiftAmt = Offset * 8; -  else -    ShiftAmt = (StoreSize - LoadSize - Offset) * 8; -  if (ShiftAmt) -    SrcVal = Helper.CreateLShr(SrcVal, -                               ConstantInt::get(SrcVal->getType(), ShiftAmt)); - -  if (LoadSize != StoreSize) -    SrcVal = Helper.CreateTruncOrBitCast(SrcVal, -                                         IntegerType::get(Ctx, LoadSize * 8)); -  return SrcVal; -} - -/// This function is called when we have a memdep query of a load that ends up -/// being a clobbering store.  This means that the store provides bits used by -/// the load but the pointers don't must-alias.  Check this case to see if -/// there is anything more we can do before we give up. -Value *getStoreValueForLoad(Value *SrcVal, unsigned Offset, Type *LoadTy, -                            Instruction *InsertPt, const DataLayout &DL) { - -  IRBuilder<> Builder(InsertPt); -  SrcVal = getStoreValueForLoadHelper(SrcVal, Offset, LoadTy, Builder, DL); -  return coerceAvailableValueToLoadTypeHelper(SrcVal, LoadTy, Builder, DL); -} - -Constant *getConstantStoreValueForLoad(Constant *SrcVal, unsigned Offset, -                                       Type *LoadTy, const DataLayout &DL) { -  ConstantFolder F; -  SrcVal = getStoreValueForLoadHelper(SrcVal, Offset, LoadTy, F, DL); -  return coerceAvailableValueToLoadTypeHelper(SrcVal, LoadTy, F, DL); -} - -/// This function is called when we have a memdep query of a load that ends up -/// being a clobbering load.  This means that the load *may* provide bits used -/// by the load but we can't be sure because the pointers don't must-alias. -/// Check this case to see if there is anything more we can do before we give -/// up. -Value *getLoadValueForLoad(LoadInst *SrcVal, unsigned Offset, Type *LoadTy, -                           Instruction *InsertPt, const DataLayout &DL) { -  // If Offset+LoadTy exceeds the size of SrcVal, then we must be wanting to -  // widen SrcVal out to a larger load. -  unsigned SrcValStoreSize = DL.getTypeStoreSize(SrcVal->getType()); -  unsigned LoadSize = DL.getTypeStoreSize(LoadTy); -  if (Offset + LoadSize > SrcValStoreSize) { -    assert(SrcVal->isSimple() && "Cannot widen volatile/atomic load!"); -    assert(SrcVal->getType()->isIntegerTy() && "Can't widen non-integer load"); -    // If we have a load/load clobber an DepLI can be widened to cover this -    // load, then we should widen it to the next power of 2 size big enough! -    unsigned NewLoadSize = Offset + LoadSize; -    if (!isPowerOf2_32(NewLoadSize)) -      NewLoadSize = NextPowerOf2(NewLoadSize); - -    Value *PtrVal = SrcVal->getPointerOperand(); -    // Insert the new load after the old load.  This ensures that subsequent -    // memdep queries will find the new load.  We can't easily remove the old -    // load completely because it is already in the value numbering table. -    IRBuilder<> Builder(SrcVal->getParent(), ++BasicBlock::iterator(SrcVal)); -    Type *DestTy = IntegerType::get(LoadTy->getContext(), NewLoadSize * 8); -    Type *DestPTy = -        PointerType::get(DestTy, PtrVal->getType()->getPointerAddressSpace()); -    Builder.SetCurrentDebugLocation(SrcVal->getDebugLoc()); -    PtrVal = Builder.CreateBitCast(PtrVal, DestPTy); -    LoadInst *NewLoad = Builder.CreateLoad(DestTy, PtrVal); -    NewLoad->takeName(SrcVal); -    NewLoad->setAlignment(SrcVal->getAlignment()); - -    LLVM_DEBUG(dbgs() << "GVN WIDENED LOAD: " << *SrcVal << "\n"); -    LLVM_DEBUG(dbgs() << "TO: " << *NewLoad << "\n"); - -    // Replace uses of the original load with the wider load.  On a big endian -    // system, we need to shift down to get the relevant bits. -    Value *RV = NewLoad; -    if (DL.isBigEndian()) -      RV = Builder.CreateLShr(RV, (NewLoadSize - SrcValStoreSize) * 8); -    RV = Builder.CreateTrunc(RV, SrcVal->getType()); -    SrcVal->replaceAllUsesWith(RV); - -    SrcVal = NewLoad; -  } - -  return getStoreValueForLoad(SrcVal, Offset, LoadTy, InsertPt, DL); -} - -Constant *getConstantLoadValueForLoad(Constant *SrcVal, unsigned Offset, -                                      Type *LoadTy, const DataLayout &DL) { -  unsigned SrcValStoreSize = DL.getTypeStoreSize(SrcVal->getType()); -  unsigned LoadSize = DL.getTypeStoreSize(LoadTy); -  if (Offset + LoadSize > SrcValStoreSize) -    return nullptr; -  return getConstantStoreValueForLoad(SrcVal, Offset, LoadTy, DL); -} - -template <class T, class HelperClass> -T *getMemInstValueForLoadHelper(MemIntrinsic *SrcInst, unsigned Offset, -                                Type *LoadTy, HelperClass &Helper, -                                const DataLayout &DL) { -  LLVMContext &Ctx = LoadTy->getContext(); -  uint64_t LoadSize = DL.getTypeSizeInBits(LoadTy) / 8; - -  // We know that this method is only called when the mem transfer fully -  // provides the bits for the load. -  if (MemSetInst *MSI = dyn_cast<MemSetInst>(SrcInst)) { -    // memset(P, 'x', 1234) -> splat('x'), even if x is a variable, and -    // independently of what the offset is. -    T *Val = cast<T>(MSI->getValue()); -    if (LoadSize != 1) -      Val = -          Helper.CreateZExtOrBitCast(Val, IntegerType::get(Ctx, LoadSize * 8)); -    T *OneElt = Val; - -    // Splat the value out to the right number of bits. -    for (unsigned NumBytesSet = 1; NumBytesSet != LoadSize;) { -      // If we can double the number of bytes set, do it. -      if (NumBytesSet * 2 <= LoadSize) { -        T *ShVal = Helper.CreateShl( -            Val, ConstantInt::get(Val->getType(), NumBytesSet * 8)); -        Val = Helper.CreateOr(Val, ShVal); -        NumBytesSet <<= 1; -        continue; -      } - -      // Otherwise insert one byte at a time. -      T *ShVal = Helper.CreateShl(Val, ConstantInt::get(Val->getType(), 1 * 8)); -      Val = Helper.CreateOr(OneElt, ShVal); -      ++NumBytesSet; -    } - -    return coerceAvailableValueToLoadTypeHelper(Val, LoadTy, Helper, DL); -  } - -  // Otherwise, this is a memcpy/memmove from a constant global. -  MemTransferInst *MTI = cast<MemTransferInst>(SrcInst); -  Constant *Src = cast<Constant>(MTI->getSource()); -  unsigned AS = Src->getType()->getPointerAddressSpace(); - -  // Otherwise, see if we can constant fold a load from the constant with the -  // offset applied as appropriate. -  Src = -      ConstantExpr::getBitCast(Src, Type::getInt8PtrTy(Src->getContext(), AS)); -  Constant *OffsetCst = -      ConstantInt::get(Type::getInt64Ty(Src->getContext()), (unsigned)Offset); -  Src = ConstantExpr::getGetElementPtr(Type::getInt8Ty(Src->getContext()), Src, -                                       OffsetCst); -  Src = ConstantExpr::getBitCast(Src, PointerType::get(LoadTy, AS)); -  return ConstantFoldLoadFromConstPtr(Src, LoadTy, DL); -} - -/// This function is called when we have a -/// memdep query of a load that ends up being a clobbering mem intrinsic. -Value *getMemInstValueForLoad(MemIntrinsic *SrcInst, unsigned Offset, -                              Type *LoadTy, Instruction *InsertPt, -                              const DataLayout &DL) { -  IRBuilder<> Builder(InsertPt); -  return getMemInstValueForLoadHelper<Value, IRBuilder<>>(SrcInst, Offset, -                                                          LoadTy, Builder, DL); -} - -Constant *getConstantMemInstValueForLoad(MemIntrinsic *SrcInst, unsigned Offset, -                                         Type *LoadTy, const DataLayout &DL) { -  // The only case analyzeLoadFromClobberingMemInst cannot be converted to a -  // constant is when it's a memset of a non-constant. -  if (auto *MSI = dyn_cast<MemSetInst>(SrcInst)) -    if (!isa<Constant>(MSI->getValue())) -      return nullptr; -  ConstantFolder F; -  return getMemInstValueForLoadHelper<Constant, ConstantFolder>(SrcInst, Offset, -                                                                LoadTy, F, DL); -} -} // namespace VNCoercion -} // namespace llvm  | 
